During the surgical implantation of femoral condylar prostheses, it is typically necessary to utilize some type of tool to hold and/or drive the prosthesis onto the distal aspect of a femur which has been resected and otherwise prepared to receive the implant. Currently, this procedure is accomplished by a variety of techniques, including the use of separate instruments for respectively holding and driving the prosthesis onto the bone. Alternatively, the same instrument has been used to both hold and drive the implant, but the aforementioned surgical approaches possess certain inherent disadvantages.
U.S. Pat. No. 3,857,389 to Amstutz describes a prosthesis holder having jaws which grasp the outer edges of a prosthetic member and are then locked in place, similar to a pair of Vise-Grip locking pliers, around the member. Similarly, the "Performance Knee", available through Kirschner Medical Products, Inc., utilizes a femoral driving instrument for impacting the prosthesis, driving it into place on a resected femur. The Kirschner instrument grips the prosthesis at notches formed along the lateral and medial edges of the condylar flanges, which is a disadvantage because the prosthesis is driven down onto the resected femur and disengaged, then another instrument is used to finish driving the prosthesis. This redundant procedural step inconveniences the surgeon and, moreover, such physical modifications to the prosthesis compromise the structural integrity of the resultant implant, and are therefore undesirable. Further, where the prosthesis is not modified as noted above, there is a further risk that the instrument jaws will impinge upon and further damage the soft tissue of the joint capsule exposed by the medical surgical incision.
Other instruments used in implanting prostheses are shown in U.S. Pat. No. Des. 230,097, disclosing a pusher used in total knee orthopedic procedures and U.S. Pat. No. 4,664,212, which shows an instrument for driving and removing a joint end of a prosthesis.
There yet remains a need for a combination holder/driver tool capable of securely gripping and positioning a femoral condylar prosthesis and driving it completely onto the resected distal femur of a patient during orthopedic surgery.